1. Field of the Invention
This invention relates generally to voice messaging systems. More particularly, it relates to a telephone answering device capable of allowing a user to delete selected portions of a recorded voice message.
2. Background of Related Art
Voice messaging systems in general, and telephone answering devices (i.e., answering machines) in particular, are useful devices for the home or office. A conventional telephone answering device operates on a single telephone line and answers an incoming call to an unused (i.e., on-hook) or even busy telephone after a desired number of rings. The telephone answering device causes the telephone line to enter an off-hook condition, then plays an outgoing greeting message to the calling party. After the outgoing greeting message, the calling party may leave a voice message on the telephone answering device. At a later time, the voice message is replayed by the user, either local to the telephone answering device or via remote connection from another telephone.
Furthermore, voice messaging in telephony has been greatly advanced in recent years by the inclusion of digital information associated with a voice message. In fact, answering or voice messaging machine designs have further benefited from the decreasing costs of non-volatile memory to the point at which digital answering machines and electronic voice mail systems are affordable and common. In these types of voice messaging systems, speech data is stored digitally, i.e., in non-volatile or volatile-with-refresh memory rather than on a magnetic tape as in older messaging machines.
FIG. 7 illustrates a conventional telephone answering device capable of answering and recording a voice message from an incoming call on a telephone line.
In particular, in FIG. 7, a telephone answering device 11 is connected to a telephone company central office 13 via a telephone line 15. A telephone line interface (TLI) 17 in the telephone answering device 11 provides the conventional isolation, DC and AC impedance as required by telephone company standards. The telephone line interface 17 also provides a ring detect signal to a controller 19. The controller 19 is typically a suitable microprocessor, microcontroller, or digital signal processor (DSP). The ring detect signal indicates to the controller 19 the ringing of an incoming telephone call on the telephone line 15.
After a desired number of ring signals, the telephone answering device 11 causes the telephone line interface 17 to place the telephone line in an off-hook state, and instructs a voice recorder/playback module 21 to play a pre-recorded outgoing greeting message over the telephone line 15 to the calling party. Upon completion of the outgoing greeting message, the calling party may leave a voice message in voice message memory 23 under the control of the controller 19.
A user of the telephone answering device 11 later retrieves the recorded voice message from the voice message memory, using the keypad 25 or other buttons or controls for selecting various modes of operation, and then deletes the voice message if desired. When deleted, the entire voice message is effectively erased from the voice message memory 23 (e.g., by allowing new voice messages to overwrite all portions of the deleted voice message).
FIG. 8 illustrates an exemplary voice message table 800 contained in one sector of the voice message memory 23. The message table 800 contains various header information relating to an underlying voice message stored in the same or linked page of voice message memory 23. Conventional header type information includes a time/date stamp 802 indicating the time and date when an underlying speech message was stored. TAG information 804 in the header contains user defined data. Typically, to maximize efficiency in the conventional digital answering machine 11, the speech data is encoded. Thus, the header includes coder information 806 identifying the type of encoding used to encode the underlying voice message data, e.g., the particular coded data rate. The new/old information 808 entry in the header of the message table 800 relates to whether or not the underlying speech message has been reviewed at least once by the user of the digital answering machine 11. The deleted/non-deleted information 810 in the header conventionally indicates whether or not the underlying voice message has been deleted by the user. The number of bytes in the last sector information 812 relates to the length of the voice message in the last sector in which the voice message is stored, avoiding replay of the unused end portion of a partially used last sector when replaying the relevant voice message. Link list information 814 in the header indicates the addresses of all sectors used to store the relevant voice message. Of course, additional header information 816 may typically be included in the message table 800.
FIG. 9 shows an exemplary sector in the voice message memory 23 containing the underlying voice message 902-908. The sector shown in FIG. 8 is the first listed in the link list 814 of the message table 800 for the underlying voice message. Zero, one or more pages of speech data 902-908 may be listed in the link list 814 of a message table 800 for a single voice message.
Unfortunately, there is limited space in the voice message memory 23 to store voice messages on a conventional telephone answering device 11. As indicated in FIG. 10, once the maximum recording time has been reached, the telephone answering device 11 will not be able to accept and record any additional voice messages. The user of the conventional telephone answering device will be required to delete or erase an entire message from the voice message memory 23 in order to receive and record additional voice messages.
Moreover, a user of a voice messaging system may occasionally receive a very long voice message. In such a case, the user may be interested in only a small portion of the very long voice message, e.g., the end portion containing a call-back telephone number. Oftentimes, a user needs to hear the general content of the voice message only once, but may not be prepared for writing down detailed information at the end, e.g., a telephone number, contact name, or an address. Using conventional telephone answering systems, the entire voice message must be retained until played back later when the user is prepared to transcribe the detailed information. Unfortunately, the retained lengthy voice message will occupy valuable memory in the limited voice message memory 23.
Accordingly, there exists a need for a method and apparatus allowing more efficient use of voice memory to provide additional capacity to store additional voice messages.
In accordance with the principles of the present invention, a deletion control module for a voice messaging system comprises a marker module adapted to delineate a recorded voice message into a plurality of portions. A selective deletion/save voice message module acts upon selected delineated portion of the recorded voice message, and leaves intact at least one undeleted portion of the recorded voice message for subsequent abbreviated playback of the recorded voice message.
A method of deleting only a portion of a recorded voice message in a voice messaging system in accordance with another aspect of the present invention comprises delineating a recorded voice message into a plurality of portions. At least one but not all of the plurality of portions of the recorded voice message are deleted.